當市(shi)(shi)電(dian)(dian)供電(dian)(dian)中斷或市(shi)(shi)電(dian)(dian)電(dian)(dian)壓超限 (±15%或±20%額定輸(shu)入(ru)電(dian)(dian)壓)時,互投裝(zhuang)置將立即投切至逆變(bian)器供電(dian)(dian),在(zai)電(dian)(dian)池(chi)組所(suo)提(ti)供的(de)直流能(neng)源(yuan)的(de)支(zhi)持下,此(ci)時,用(yong)戶負載所(suo)使用(yong)的(de)電(dian)(dian)源(yuan)是通過EPS的(de)逆變(bian)器轉(zhuan)換的(de)交流電(dian)(dian)源(yuan),而不是來自市(shi)(shi)電(dian)(dian)